Pick over the crabmeat to remove any shell or cartilage, trying not to break up the chunks too much.

In a large bowl, combine all of the ingredients except for the butter and olive oil. Moisten hands with a little water and shape the mixture into eight fat ball-like cakes. (They will flatten slightly during cooking.) Place them on a baking sheet lined with wax paper. Cover with plastic wrap and refrigerate for at least 1 hour.In a large skillet, heat the butter and oil over medium-high heat. Carefully lay the crab cakes into the butter and oil and fry until crusty and browned, about 3 to 4 minutes on each side.